Defects and strain studies in semiconductor multilayers

Abstract

The study of strain, lattice mismatch and/or misfit defects generated in superlattices by ion channeling has increased enormously during the recent years. The strained layer structures based on GaAs have been studied theoretically and experimentally. The theoretical work consists of calculating catastrophic dechanneling resonance (CDR) on In0.1Ga0.9As/GaAs superlattices along the (110) plane. The incident beam is He4 and the study is carried out using Moliere potential. The experimental work, recently undertaken to characterize such multilayers grown by OMVPE techniques, shows that RBS/Channeling is a sensitive technique for strain measurements. The minimum yield from small concentrations of indium in the InGaAs provides reliable information about the crystallinity of the sample. The shift in the position of the minimum yield for the overlayer is used to extract the strain information. The effects of defects resulting from the strain relaxation are also discussed for their dechanneling effects.